Conventionally, animal fibers such as wool have been widely used because they are high in elasticity and thermal insulation. However, the use of animals fibers have numerous disadvantages such as poor dye penetration, milling caused by interwinding of scales, bad feeling to the skin and the like, due to the presence of scales on the surface.
As a method for improving the milling property, namely shrink-resistant finish, it has been known to remove the scales partially with a chemical treatment. However, this chemical treatment cannot remove the scales completely and has a disadvantage of deteriorating the feeling of the fiber.
Animal fiber (hair) such as wool differs in quality and extent of adhesion of impurities according to the site even in a sheet of fleece. Hence, in order to use animal fiber efficiently, it should be classified into three or four grades. After the classification, the animal fiber is scoured and then subjected to conventional processes such as carding. In general, it has been necessary to apply chemical treatments in the scouring step to remove impurities (grease, sweat, dirt, etc.) adhered on the animal fiber. For example, a complex scouring process is applied by using chlorinated solvents and detergents. However, such a scouring process has problems not only in operation but also in the waste disposal and damage of the fiber.
Recently, environmental pollution problems have become a serious and important issue. The development of a method for carrying out the scouring process of animal hair or a method for improving the milling property without the use of chemicals which cause environmental pollution is needed.
The subject of the invention is to provide a method for physically and efficiently improving the scouring process and the milling property of animal fibers without the use of chemicals which cause environmental pollution.